Unit air conditioner



Feb. 9, 1943. I c. N. DEVERALL UNIT AIR COND IIIONER Filed Aug. 2, 1940'3 Sheets-Sheet 1 BY)? wNTOR TTORN EY 3 Feb. 9, 1943. N. DEvERA-LL2,310,222

UNIT AIR CONDITIONER Filed Aug. :2, 1940 s Sheets-Sheet 2 ATTORN EYS WPatented Feb. 9, i943 UNIT Am CONDITIONER Charles N. Deverall, Buffalo,N. Y., assignor to Niagara Blower Company, New. York, N.

corporation of New York Application August 2, 1940, Serial No. 349,61815 Claims. (01. 99-259) This invention relates to a unit air conditionerand more particularly to such a unit for maintaining the propertemperature, humidity, pressure, air movement of both primary andsecondary air, and smoke density of the smoke laden air in a smokehousein which food products are being cured and smoked although the unit airconditioner forming the subject of the invention can also be employed inthe processing of other mate- I rials, such asin drying leather.

One of the principal objects of the invention is to provide a compactand simple air conditioning unit containing the necessary mechanisms forsupplying air to a smokehouse or similar enclosure ,in which materialsare processed; varying the amount and velocity of the air so supplied toobtain the desiredmovement of both th primary and secondary air withinthe enclosure; introducing smoke to the air so supplied when required;heating the air so introduced when required; withdrawing air from theenclosure to maintain the desired static pressure in the smokehouse;returning a part of the airso withdrawn, together with outside air, tothe smokehouse to maintain the desired humidity therein; and humidifyingthe air supplied to the enclosure, when required By the provision ofthese various instrumentalities in a single compact unit, installationof the equipment is greatly simplified and the greater part of thefabrication can be efiected at the factory instead of in the field; heatlosses are reduced, resistance to air flow is minimized; the danger ofleakage. can be completely eliminated; the amount ,of floor and overheadspace required for the equipment can be greatly reduced; the

amount of materials necessary for the equipment can be reduced therebylowering the cost of the: equipment and permitting of the use of morecost;

ly materials and finer finishing inspection and repair of the equipmentis facilitated especially where a battery of identical units are in'usein a packing plant; and anextremely sensitive control of the conditionand movement of the air within the smokehouse can be readily obtained.

Another object of the invention is to provide such a unit which issubstantially the same height as the smokehouse and can be placed flushagainst the rear wall of the smokehouse thereby to simplify and reducethe amount of ductwork necessary to connect the unit with the overheadducts of the smokehouse.

, Another object is to provide such a unit which can also be mountedhorizontally thereby to permit of mounting the unit on top of orunderneath the smokehouse where the conditions encountered render suchmounting of the unit desirable.

Another purpose is to provide such a unit which is'composed of tworeadily separable major sections thereby to facilitate shipping of theunit to the location and to facilitate the transportation of the unitthrough doors, corridors and elevators in getting the unit into locationwithin the packing plant.

, Another object is to provide such a unit in which all danger ofoutside air, return air, and smoke laden air short circuiting in'theunit is avoided thereby accurate control of the conditions within thesmokehouse.

Another aim is to introduce the smoke laden air into the unit in suchmanner as to reduce to a minimum the fouling of the equipment bycreosote deposits thereby to eliminate the necessity of frequent cleaninparticularly of the finned heating surface from which a creosote depositis diflicult to remove.

Another object is to provide such a unit in which all of the interiorparts of theunit are readily accessible through conveniently removableaccess panels thereby facilitating inspection, adjustment, repair andcleaning of the unit when required.

Another object of the invention is to provide such a unit which ismounted on removable feet to facilitate the transportation of the unitto its charge of the fan from either of two diametrically opposite sidesof the casing thereby rendering the unit readily-adaptable toinstallation when peculiar conditions are encountered. I

Another object is to provide such a unit from which any water ofcondensation is readily drained and in which water for humidification isreadily introduced.

Another object is to arrange the motor controlled dampers in theductwork between the unit and the smokehouse to provide flexibility insupplying any make or form of control desired by the packer. I v 3 otherobjects and advantages of the unit form. ing the subject of thisinvention will appear from drawings wherein:v

Fig. 1 is a side elevation of a smokehouse the subject of the presentinvention and showing a part of the smokehouse broken away to disclosethe interior tracks and overhead ductwork thereof.

Fig. 2 is a vertical transverse section through the smokehouse, thissection being taken on line 2-2, Fig. 1.

Fig. 3 is a vertical section through the air conditioning unitillustratedin Figs. 1 and 2, this section being taken on line 3 -3, Fig.4. v

Fig. 4 is a vertical section taken on line 4-4, Fig. 3.

Fig. 5 is a side elevation of the air conditionin: unit.

Fig. 6 is a diagrammatic representation of the control instruments usedin connection with the air conditioning unit to regulate thetemperature,humidity and static pressure of the air within the smokehouse.

While the air conditioning unit embodying the present invention can beused in connection with any type of smokehouse, the smokehouseillustrated is of the insulated panel type of construction having sidewalls "I, II, a roof l2, a rear wall l3 and a front wall l4 having anaccess door l5 which can be mounted in any suitable manner. Thesmokehouse is shown as provided with an overhead track 20 which issuspended in any suitable manner from rods 2|, these rods beingpreferably suspended from the ceiling (not shown) of the packing plantso that the smokehouse can be made of light construction. With such asmokehouse the food products to be cured and smoked can be hung fromtrees (not shown) suspended from the overhead track 20 or can be hungupon trucks (not shown).

The air is introduced into the smokehouse through a central overheadduct 24 which extends through the rear wall l3 of the smoke: house. Thisduct is provided within the smokehouse with a plurality of downwardlydirected nozzles 25 which direct the air downwardly. After passingaround the produce the air so discharged is withdrawn through openings28 in the undersides of overhead ducts 21. Each of these ducts 21 isshown as arranged alongside oneof the side walls III, II ofthesmokehouse and extends through. the rear wall l3 thereof.

The air conditioning unit forming the subject of the present inventionincludes a casing comprising an upper casing section A and a lowercasing section B,- the casing and its component sections being ofbox-like rectangular form. The smokehouse and the unit are arranged backto back and hence the upper casing section A includes arear wall 38,side walls 3|, 32, a front wall 33 and a top wall 34, these walls beingsuitably reinforced with angle bars. Similarly the lower casing sectionBincludes a rear wall- 40,

. side-walls 4|, 42, a front wall 43 and a bottom wall 44, these wallsbeing likewise suitably reinforced with angle bars. The lower casingsection B is supported by removable feet 45 and its lower end is formedto provide a drain pan provided with a drain 46. The two sections A andB are provided around the opposing edges oftheir side and=front wallswith horizontal angle bars, indicated generally at 41, these angle barsof the two sections being arranged back to back and providing aconvenient means for bolting or otherwise securing the two sections Aand B together.

The upper section A houses the scroll 50 of 'a supply fan, indicatedgenerally at 5l,this scroll 7 equipped with the air conditioning unitforming having inlets 52 at its opposite sides and an outlet 53extending through an opening 54 at the upper end of the rear wall 30 ofthe upper casing section A. The fan wheel 55 arranged within the scroll50 is mounted on a horizontal fan shaft 55, the ends of which aresupported by bearings 51 suitably mounted on the side walls 3| and 32 ofthe upper section A of the casing. The supply fan is shown as beingdriven by an electric motor 68, mounted on the top wall 34 of the casingand as having a pulley 6| on its motor shaft, this pulley beingconnected to a pulley 62 on the fan shaft 56 by a drive belt 63. Theoutlet 53 of the supply fan is adapted to be directly connected with therear end of the central overhead supply duct 24 of the smokehouse sothat the air and smoke delivered by the supply fan is introduced intothe smokehouse throughthe downwardly directed nozzles 25. The scroll 50is also preferably provided with an access door 58 for cleaning the fanwheel 55.

Opposite the opening 54 through which the outlet 53 of the fan projects,the front wall 33 of the upper casing section A is formed to provide anopening 64 surrounded by a flanged neck 65, this opening having aremovable cover 86 which permits of ready access to the chamber in whichthe fan is located.

Immediately below the flanged neck 65 a smoke inlet opening 61 isprovided, this opening being surrounded by a flanged neck 68 whichpermits of attachment to a' smoke pipe 69, this smoke pipe leading fromthe usual smoke ,pot (not shown) which supplies smoke for the operationof the smokehouse. The volume of smoke drawn into the unit through'thesmoke pipe 89 is controlled by dampers Ill in this pipe, these dampersbeing under the manual control of a hand lever 1|. section A ahorizontal perforated pipe 12 is provided, this pipe being perforated asindicated at 13 and being adapted to be connected with a water or steamsupply pipe 14 for humidifying the air drawn into the fan 5| when thisbecomes necessary.

At the extreme open upper end of the lower casing section B a pluralityof volume control dampers are provided. Each of these dampers isjournaled along its central horizontal axis to the side walls 4| and 42of the lower casing section B, as best shown in Fig. 4 and areinterconnected to work in unison by a horizontal bar 16. The dampers areadjusted by means of a hand lever 11 arranged exteriorly of the casingand connected to the shafts of one of the dampers. This hand lever 11traverses a segment 18 on the side wall 42 of the lower casing sectionB, this segment being so designed that the hand lever 11 can be set inany adjusted position and hence hold the volume control dampers 15 insuch adjusted position.

A suitable number of heating coil sections, indicated generally at 88.are arranged in the lower casing section B. These heating coil sectionscan be provided in any number having any desired amount of heatingsurface and are shown as being three in number, each of the coilscomprising a tubular inlet header 8| having a pipe 82 for supplyingsteam, a tubular outlet header 83 having a condensate outletpipe 84 andthe I On the oppositeside of the upper casingviding access to the coilsections 88.

Each of the three coil sections 88 is shown asbeingindependentlyremovable from the lower casing section B "and for this purpose thesteam connections 82 and 84 for these coils pass through a removableaccess plate 88 which is secured to the side wall 4| ofthe lower casingsection B around an opening 89 which is of such size as to permit thecoil sections 88to be slid out of the casing: after the plate 88 hasbeen removed.

To facilitate this removal the individual coil sections' are supportedwithin the casing in the '85 adjacent their return bends, this platebeing shown as flanged at its lower end to slidably rest upon the samepair of angle bars 89.

To. permit of ready access to the coil sections I 88 for'the purpose ofinspecting or cleaning them while in place; the front wall 43 isprovided with a large rectangular opening 9| which is flanged around themargin, as indicated at 92, and to this flange is secured a removablepanel 93 profBeloW-the coil sections 88 the lower casing section Bisformed to provide a supply chamber 95 for outside and return air," thelower wall of this/supply chamber being formed by a horizontal'baflleplate 98 which is secured at its opposite ends to the rear and frontwalls 48, 43 of the lower casing section B, as? best shown in Fig. 3,butis spaced from the side walls H, 42 thereof so as to provideopenings91. Outside air is admitted to thissupplychamber 95 through aninlet I88 which is arranged in'the front wall 43 of e'lower casingsection B and discharges the outside 'airon top of the .baiile plate 98.To prevent the bypassing of outside air this inlet I88 is narrower in ahorizontal direction than the bailie plate 98, as best illustrated inFig. 4. This outside air inlet I88 is connected to an outsideair ductI8I.

Below the baille plate 9.8 the lower casing secl85; In thisgexhaustchamber is arranged the scroll I86 of a static pressure fan, indicatedgenerally at I81, this scroll having inlets I88 at its opposite sidesand an outlet I89 extending through an opening H8 in the lower part ofthe rear wall 43. of the lower casing section B. The

fan wheel III arranged within the scroll,I88 is mounted on ahorizontalfan shaft II2, the ends oi which are supported by bearin s II3 suitablymounted on the'side walls 4! and 42 of the lower casing section B of thecasing. The static pressure fan is shown as being driven by an electricmotor 5 mounted on a removable bracket II8 projecting outwardly from thelower end of the side wall H of the'casing. This motor is shown ashaving a drive pulley 1 on its drive shaft.

this pulley-being connectedto a pulley II8 on.

the fan shaft I I2 by a drive belt I I9. The outlet lator I32 andthrough this regulator controls the .tion B is formed toprovide anexhaust chamber the other motor 0 close the corresponding set of.

'42 of-the'lower casing section B is provided with a return air inletI25, each of these inlets leading into the corresponding space 91 ateach side of the baflle plate 98 so that the two inlets I25 areintersected by the plane of this baille plate 98, as best shown in Fig.4. Each of these inlets I25 is connected by a duct I28 with the end ofthe corresponding overhead side return duct 21 of the-smokehouse, asbest shown in Figs. 1 and 2. Referring to the diagrammaticrepresentation of the control instruments used in connection with theair conditioning unit as above described toregulate the temperature,humidity and static pressure of the air within the smokehouse, the

numeral I38 represents -"an air pressure supply line through which airis supplied at, say 15 pounds pressure, to a static pressure regulatorI3 I which can be arranged within the smokehouse and to a double penrecording regulator I32. The numeral I33 represents an automatic waterpan 'of a wet bulb thermostat I34 the sensitive part of which is encasedwith acovering of absorbent material I35, the lower part of which isimmersed in the water contained in the automatic water pan I33. Theautomatic water pan is also arranged to support a dry bulb thermostat-I38 and the automatic water pan can be arranged in one of the returnair ducts I28 so that the sensitive parts of the wet and dry bulbthermostats are responsive to the wet and dry bulb temperature of theair within the smokehouse.

The control line I48 from the dry bulb thermostat I38 leads to thedouble pen recording regu- -tor controls the air pressure in a line I48leading to a diaphragm valve I41 which controls the supply of water orsteam to the perforated humidifying pipe 12 arranged in the upper casingsection A of the air conditioning unit. This air pressure line I48.alsoleads to a motor I48 controlling a set of dampers I49 in one or both ofthe return,

air ducts I28 and also leads to amotor I58 controlling a set of dampersI5I in the outside air ducts IN. The motors I48 and I58 work inbpposition to each other,the change in pressure in the line I48, undercontrol of the wet bulb thermostat I34, actuating one of these motors toopen the correspondin set of dampers and actuating dampers.

The outlet line I55 from thestatic pressure regulator I3I controls thedamper motor I58 controlling a set ofjda'mpers I51'in the exhaust ductInstallation and operation of the air I unit v conditioning motor 88-for the supply fan can be readi1y-re--.-

' ulated by the handle 11.

moved; the bracket IIB carrying the static pressure fan motor II5 canalso be removed; and the removable feet 45 can also be removed. By this,means not only is it possible to ship the unit in a knockdown conditionbut the assembly of the unit is facilitated inasmuch as the two majorsections are of such weight that they can readily be set in position.Further the removability of the feet 45 permits of adjusting the overallheight of the unit and its duct openings as may be desired to suit theparticular conditions encountered, feet of the desired height beingsupplied for this purpose.

In installing the, unit air conditioner, the unit can be placed directlyup against therear wall of the smokehouse and the outlet 53 of thesupply fan placed directly in the central overhead'inlet duct 25 of thesmokehouse as illustrated, thereby effecting a substantial saving induct work and avoiding the danger of leakage, loss of heat, and

power loss through resistance to air flow. It the conditions surroundingthe installation render it desirable to arrange the unit horizontally ason the roof of the smokehouse or in an existing smoke pit below thesmokehouse, this can readily be done with the unit. If further peculiarconditions render it desirable to have the supply fan 5| discharge inthe opposite direction from that shown, it will be seen that the entireupper sec tion A of the casing can be turned completely around and suchreversal readily efiected, this requiring but a slight alteration in theattaching flanges 41.

The various motor control dampers I49, I,5I and I51 are not, however,built into the unit. These motor operated dampers are-purposely mountedin the corresponding ducts leading to or from the unit in order toprovide flexibility in s pplying any make or form of control desired bythe packer. I

When once installed the air conditioning unit occupies very little floorand overhead space and is connected with a minimum amount of ductwork.

In the operation of the air conditioning unit smoke is supplied from asuitable smoke pot (not shown) through the smoke pipe 69 into the upper,section A of the unit, the admission of the smoke being under manualcontrol of the dampers 10 regulated by the hand lever N. This smoke isdrawn into the inlet 52 of the supply fan 5I together with air drawnfrom the lower section B of the air conditioning unit under control ofthe vol-1 ume control dampers 15 which are manually reg- The smoke ladenair so drawn into the fan 5| is discharged through the outlet 53 of thefan directly into the overhead central duct 24 arranged within thesmokehouse and in this air, this density being determined by theproportional adjustment of these volume control dampers and the smoke'dampers 10.

The smoke laden air so discharged downwardly through the nozzles 25travels around the prod- .ucts contained within the smokehouse to cureand smoke the same. A distinct secondary movement of the air within thesmokehouse is also obtained "so as to insure adequate air-movement houseis regulated through, a suitable adjustto' contact with all surfaces ofthe produce contained within the smokehouse. The air is withdrawnthrough the outlet openings 26 in the bottom of the overhead side outletducts 21 arranged within this smokehouse and is drawn downwardly throughthe ducts I26. past the control dampers I49 into the return air openingsI25 in the lower part of the lower casing section B of the airconditioning unit. These openings are arranged to discharge into thespaces 91 at the sides of the battle plate 96 and hence a part of thisreturn air enters the supply chamber 95 above this baflle and the otherpart enters the exhaust chamber I05'below this plate 96. The exhaustchamber I05 is exhausted by the static Pressurefan I01, the inlets I09of which are arranged in this chamber I05 and the outlet I09 of whichdischarges into the exhaust duct I20, this discharge being under controlof the dampers I51.

Outside air is also drawn into the supply chamber 95. This outside airis under control 01' the motor operated dampers I 5I in the fresh airduct IOI leading to the-outside air inlet opening .I00 to this supplychamber 95. In order to prevent short circuiting of this outside air tothe exhaust chamber I05, this air is introduced immediately above thebaffle 96 at its center and parallel with its major axis so that thereis no'danger of this outside air flowing down through the openings 91 atthe sides of the baflle plate 96 along with the return air being ex-.

hausted from the unit, as previously described.

The outside air and the return air drawn into the supply chamber 95mixes and passes up through the several coil sections 80 contained inthe upper part of the lower section B of the unit and is heated therebywhen heat is required in the air admitted to the smokehouse. This heatedmixture of return and outside air is then drawn past the volume controldamper 15 by the supply fan 5|, as described at the start of thedescription of the operation, this heated mixture being also mixed withthe smoke supplied 1 through the smoke inlet 61.

, outlet duct I20 from the static pressure fan I01 7 the smoke isdischarged downwardly through the chokes oil the quantity of airrelieved from the smokehouse and hence increases the pressure of the airwithin the smokehouse. Conversely; the opening ofpthese dampers I51permits a less restricted discharge of the air and hence decreases thepressure of the air within the smokehouse.

Thetemperature maintained within the smokement provided in the doublepen recording regulator I32. When the temperature within the smokehousedrops below this setting, the'dry bulb thermostat I36 in one of theoutlet ducts I25 actuates the double pen recording regulator I32 toadjust the air pressure in its outlet line I to open the diaphragm valveI42 and admit an increased amount of steam to the bank or heating coilsections in the lower section B or the heating 'coil perature of thecoils restoring the temperature of the air within the smokehouse to thesettin of the double pen recording regulator. Conversely, a rise intemperature in the smokehouse above the setting of the double penrecording regulator eiiects a shutting off of the diaphragm valve I42and hence a decrease in the amount of steam admitted to the heating coilsections 80.

The humidity, preferably the absolute humidity, maintained withinthesmokehouse is regulated through a suitable adjustment provided in thedouble pen recording regulator I32. When the humidity in the smokehouserises above the setting of the double pen recording regulator I32, thewet bulb thermostat I34 in one of "the outlet ducts I26 actuates thedouble pen recording regulator I32 to adjust the air pressure in itsoutlet line I46 to open the damper II in the outside air duct IIlI,through the medium of the damper motor I50, and at the same time toclose the dampers I49 in the return air duct or ducts. I26 through themedium of the damper motor I48. This proportionate openingof the outsideair dampers and closing of the return air dampers serves to admit agreater proportion of outside air and since the humidity of the outsideair is always lower than the humidity maintained within the smokehouse,this opening of the outside air dampers and closing of the return airdampers serves to lower the humidity of the air within the smokehouse.Conversely, when the humidity in the smokehouse drops slightly below thesetting of the double pen recording regulator I32, the wet bulbthermostat I34 actuates the double pen recording regulator I32 to adjustthe pressure in its outlet line I45 to open the outside air dampers I5Iand close the return air dampers I49. Thus, the propor-' tion of humidreturn air in the mixture delivered to the smokehouse is increased andhence the low humidity therein restored to the setting of the double penrecording regulator I32.

If the humidity in the smokehouse drops below the capacity of theoutside and return air dampers I5I and I49 to control, the wet bulbthermostat I34 actuates the double pen-recording regutions 80 can beslid out or the side of the unit in the manner of a drawer.

Where the smokehouse is operated under conditions demanding a highhumidity, a certain amount of condensation necessarily occurs in thebottom of the air conditioning unit through the contact of the humidreturn air with the relatively cool walls ofthe unit. This water ofcondensation flows down these walls into the pan formed at'the bottom ofthe lower section B of the casing and out through the drain 46.

From the foregoing it will be seen that the present invention provides avery simple and compact air conditioning unit containing the necessarymechanisms for supplying air into the smokehouse or similar enclosure;varying the amount and velocity of the air so supplied to obtain thedesired movement of both the primary and secondary air therein;introducing smoke to the air so supplied when required; heating the airso introduced when required; withdrawing air from the enclosure tomaintain the desired static pressure therein; returning a part of theair so withdrawn together with outside air to maintain the desiredhumidity in the enclosure; and hu- 'midifying the air supplied to theenclosure by the addition of water or steam when required. By

the provision of these instrumentalities in a single compact unit theproblem of installation is reatl simplified, the cost of the equipmentgreatly reduced and losses also eliminated. The-air conditioning unit asa whole is also renderedadaptable to meet various installationconditions. At

the same time a control of. increasedaccuracy can be obtained,particularly in the elimination of the leakage of heat or air and in theelimination of any danger of by-passing of air in the unit.

I claim as my inventiqn:

1. An air conditioning unit for conditioning the air in enclosures inwhich materials are proc essed, comprising a casing, a supply fansecured Y to said casing and having'its inlet co eating with theinterior thereof and i s outlet adapted to deliver air to saidenclosure, means for admitting return air from said enclosure into saidcasing at the end thereof opposite said suplator I32 to adjust the airpressure in its outlet vided in the casing. Thus, by removing the panelas in the mint wall of the unit the sup ly mi 1| is rendered entirelyaccessible tor cleaning the same or making any'minor repairs. Similarly,the removal of the large panel 93 in this same front wall or the casingrenders the entire bank of heating coil sections'accessible forcleanminor' repairs and renders the volume control dampers "I5accessible for similar purpom It more extensive repairs or cleaning ofand outlet pipes 32 and for these sections can be disconnected andtheplate ll removed so that any one or-all or the heating coilsec-'sections ll is required, the inletmeans for, admitting outside air intosaid casing,

ply fan, means adjacent said return air admitting means for admittingoutside air into said casing, heating coils arranged in said casingbetween said supply fan inlet and said return, and outside air admittingmeans for heating the retumand outside air drawn'into said supply fan, avolume control damper housed in said casing and controlling the totalvolume of said return and outside air drawn through said casing and intosaid supply fan, and means for regulating said volume controldamper.

' 2. An air conditioning unit for conditioning the air in enclosures inwhich materials are processed, comprising a casing, a supply fan securedto said casing" and having its. inlet communicating with the interiorthereof and its outlet adapted to deliver air to said enclosure, meansfor admitting return air from said enclosure into said casing at the endthereof opposite said supply tan, means adjacent said returnairadmitting heating coils arranged in said casing betweensaid supplyfan inlet and said return and outside air admitting means for heatingthe return and outside air drawn into said supply fan, a volume control'damper housed-in said casing intermediate said heatingeoils and saidsupply fan inlet and controlling the total volume of said'retum andoutside air drawn through said casing and into said supply fan, andmeans for regulating said volume control damper.

3. An air conditioning unit for conditioning the air in enclosures inwhich materials are processed, comprising a casing, a supply fanarranged at one end of said casing and having its inlet communicatingwith the interior thereof and its outlet arranged to deliver air to saidenclosure, means arranged in said casing at the end thereof oppositefrom said supply fan and forming a supply chamber and an exhaust chambertherein, said supply chamber being in communication with said inlet ofsaid-supply fan Q air in enclosures in which materials are processed,comprising an elongated casing, a supply fan arranged at one end of saidcasing and having its inlet communicating with the interior thereof andits outlet arranged to deliver air to said enclosure, a baflle plateextending transversely across the interior of said casing at theopposite end of said casing from said supply fan and forming an exhaustchamber at the extreme and or said casing and a supply chamberintermediate said exhaust chamber and said inlet of said supply fan,said supply chamber being in communication with said inlet of saidsupply fan and said chambers being in communication with each other,means for admitting outside air to said supply chamber, means foradmitting return air jointly to said supply and exhaust chambers, anexhaust fan discharging said return air from said exhaust chamber andheating coils arranged in said casing between said inlet of said supplyfan and said supply chamber for heating the outside and return air drawninto said supply fan. 5. An air conditioning unit for conditioning theair in enclosures in which materials are processed, comprising anelongated casing, a supply fan arranged at one end of said casing andhaving its inlet communicating .with the interior thereof and its outletarranged to deliver air to said enclosure, a baflie plate extendingtransversely across the interior of said casing at the opposite end ofsaid casing from said supply fan and forming an exhaust chamber at theextreme end of said casing and a supply chamber intermediate saidexhaust chamber and said inlet of said supply fan, said supply chamberbeing in communicationwith said inlet of said supply fan and said baiileplate being spaced from one wall of said casing to provide an openingestablishing communication between said chambers,.means for admittingoutside air to said supply chamber parallel with said baflle plate,means for admitting return air to said opening between said baflie plateand said one wall of said casing, an exhaust fan for'discharging saidreturn air from said exhaust chamber and heating coils arranged in saidcasing between said inlet of said supply fan and said-supply chamber forheatingthe outside and'return air drawn into said supply fan. 6. An airconditioning-unit for conditioningthe air in enclosures in whichmaterials are proccommunicating with the interior thereof and its outletarranged to deliver air to said enclosure;

I means arranged in said casing at the end thereof opposite from saidsupply fan and forming a supply chamber and an exhaust chamber therein,

said supply chamber being in communication with said inlet of saidsupply fan and said chambers being in communication with each other,means for admitting outside air to said supply chamber, means foradmitting return air from said enclosure jointly to said supply andexhaust chambers, an exhaust fan secured to said casing and dischargingsaid return air from said exhaust chamber, heating coils arranged insaid casing between said inlet of said supply fan and said supplychamber for heating the outside and return air drawn into said supplyfan, a volume control damper housed in said casing intermediate saidheating coils and said supply fan inlet and controlling the total volumeof said return and outside air drawn through said casing and into saidfan, and means for regulating said volume control damper.

7. An airconditioning unit for conditioning the air in enclosures inwhich materials are processed, comprising an elongated casing, a supplyfan arranged in one end of said casing and having its outlet arranged todeliver air to said enclosure, means arranged in said casing at the endthereof opposite from said supply fan and forming a supply chamber andan exhaust chamber, said exhaust chamber being in communication withsaid supply chamber and said supply chamber being in communication withthe inlet of said fan, means for admitting outside air to said supplychamber, means for admitting return air from said enclosure jointly tosaid supply and exhaust chambers, an exhaust fan discharging said returnair from said exhaust chamber and heating coils arranged in said casingbetween said supply chamber and said supply fan for heating the outsideand return air drawn:

into said supply'fan, said casing being composed of two major separable.sections, the first comprising the end of said casing containing saidsupply fan and the second comprising the end of said casing containingsaid heating coils and supply and exhaust chambers.

8. An air conditioning unit for conditioning the air in enclosures inwhich materials are processed, comprising an elongated casing, a supplyfan arranged in one end of said casing and having its outlet arranged todeliver air to said enclosure, means arranged in said casing at the endthereof opposite from said simply fan and forming a supply chamber andan exhaust chamber, said exhaust chamber being in communication withsaid supply chamber and said supply chamber being in communication withthe inlet of said fan, means for admitting outside air to said supplychamber, means for admitting return air from said enclosure jointly tosaid supply and exhaust chambers, an exhaust fan discharging said returnair from said exhaust chamber, heating coils. arranged in said casingbetween said supply chamber and said supply fan for heating the outsideand return air drawn into said supply fan, a volume control damperarranged in said casing intermediate said heating coils and said acrea esections, the first comprising. the end of said casing containing saidsupply fan and the second comprising the end of said casing containing'the air in enclosures. in which ,materials are processed, comprising acasing, a supply fan secured to said casing and having its inletcommunicating withv the interior thereof and its means for admittingreturn air from said enclosure into said casing at the end thereofopoutlet adapted to deliver air to said enclosure,

of said supply fan and said supply chamber for posite said supply fan,means adjacent said rev.

turn air admitting means for admitting outside air into, said casing,heating coils in said casing between said supply fan inlet .and saidreturn and outside air admitting means for heating the return andoutside air drawn into said supply fan, a volume control damper housedin said casing and controlling the total volume of said return andoutside air drawn through said casing and into said supply fan, meansfor regulating said volume control damper and means arrangedbetweensaidvolume control damper and said supply fan for humidifying the air drawninto said supply fan. i

10. An air conditioning unit for conditioning and supplying smoke ladenair to smokehouses,

comprising a casing, a supply fan secured to said casing and havingits-inlet communicating with the interior thereof and its outlet adaptedto deliver air to said smokehouse,-means for admitting return-air fromsaid smokehouse into said casing at the end thereof opposite said supplyfan, means adjacent said return air admitting means for admittingcasing, heating coils arranged in said casing between said. supply faninlet and said return and outside air admitting means for heating thereturn and outside air drawn into saidsupply fan, and means arrangedbetween said coils and said supply fan for admitting smoke to saidreturn and outside air drawn into the inlet of said supply fan. I 11. Anair conditioning unit for conditioning and supplying smoke laden airtosmokehouses,

comprising a casing, a supply fan secured to said casing and having itsinlet communicating with the interior thereof and its-outlet adapted todeliver air to said Smokehouse, means for adoutside air into saidopposite from said supply fan and forming a supply chamber and anexhaust chamber therein, said supply chamber being in communication withsaid inlet of said supply fan and said chambers being in communicationwith each other; means for admitting outside air tosaid supply chamber,means for admitting return air jointly to said supply and exhaustchambers, an exhaust .fan secured to said casing and discharging saidreturn air from said exhaust chamber, heating coils arranged in saidcasing between said inlet heating the outside and return air drawn intosaid coils and supply fan for admitting smoke to said return and outsideair drawn into said supply fan.

13. In apparatus for conditioning the air in an enclosure in whichmaterials are processed, and having a casing, a supply fan arranged atone end of said casing and having its inlet communieating with theinterior thereof and' having its outlet arranged to deliver air to saidenclosure, means arranged in said casing at the end thereof oppositefrom said supply fan and forming a supply chamber and an exhaust chambertherein, said supply chamber being in communication with said inlet ofsaid supply fan and said chambers being in communication with eachother,

- admission of said outside air to said supply chamber, means foradmitting return air from said enclosure jointly to said supply andexhaust chambers, a return air damper controlling the admission of saidreturn air to said chambers, an exhaust fan secured to said casing anddischarging said return air from said exhaust chamber, an exhaust dampercontrolling the discharge of return air by said exhaust fan, and heatingcoils arranged in said casing between said inlet of said supply fan andsaid supply chamber for heating the outside and return air drawn intosaid supply fan; the combination of means responsive to the dry bulbtemperature of the air in the enclosure and controlling the admission ofheating medium to said heating coils, means responsive to the humidityof the air in said enclosure and controlling the relative mitting retum'air from said -smokehouse into said casing I supply fan, means adjacentsaid return air admitting means for admitting outside air intosaidcasing, heating coils arranged in said casing at the end thereofopposite said supply fan for admitting smoke to said return and outsideair drawn into the inlet of said suppm fan, a volume control damperarranged in said casing intermediate said heating coils andsaid smokeadmitting means and controlling the volume of said outside and returnair drawn into said supply fan and means for regulating said volumecontrol damper:

12. Anair conditioningunit for conditioning and supplyingsmoke laden airto smokehouses, comprising a casing, a supply fan arranged at one end ofsaid' casing and having its inlet cominunicating with the interiorthereof and its outlet arranged to deliver air to said smokehouse,

positions of said return air and outside air damp.-

ers to control the humidity of the air within the enclosure and meansresponsive to the pressure of the air within said enclosure 'andcontrolling said exhaustvdamper to maintain apredetermined air pressurein said enclosure.

14. In apparatus for conditioning and supplying smoke laden air tosmokehouses, and having a casing, a supply fan arranged at one end ofsaid casing and having'its inlet communicating with the interior thereofand having its outlet arranged to deliver air to said smokehouse,-

meansv arranged in said casing at the endthereof opposite from saidsupply fan and forming a supply chamber and'an exhaust chamber therein,said supply chamber being in communication with said inlet of saidsupply fan and said chambers being in communication with each other,'means for admitting outside air to said supply chamber, an outside airdamper-controlling the admission of said outside air to said supplychamber, means for admitting return air-from said 'smokehouse Jointly tosaid supply and exhaust chambers, a return air damper controlling,

- the admission of said return air to said chambers,

means arranged in said casing at the end thereof an exhaust fan securedto said casing and discharging said return air from said exhaustchamher, an exhaust damper controlling the discharge of return air bysaid exhaust fan, heating coils arranged in said casing between saidinlet of said supply fan and said supply chamber for heating the outsideand return air drawn into said supply fan, a volume control damperarranged in said casing intermediate said heating coils and said supplyfan inlet and controlling the volume of said return and outside airdrawn into said supply fan, means for regulating said volume controldamper, means arranged between said heating coils andsupply fan foradmitting smoke to said return and outside air drawn into said supplyfan, a smoke damper controlling the admission of said smoke to saidsmoke admitting means, means forregulating said smoke damper, and meansresponsive to the dry bulb temperature of the air in the smokehouse andcontrolling the admission of heating medium to said heating coils; thecombination of means responsive to the humidity of the air in saidsmokehouse and controlling the relative positions of said return air andoutside air dampers to control the, humidity of the air in saidsmokehouse and means responsive to the pressure of the air in saidsmokehouse and controlling the position of said exhaust damper tomaintain a predetermined air pressure in .said smokehouse.

15. In apparatus for conditioning and supplyingsmoke laden air tosmokehouses, and having a casing, a supply fan arranged at one end ofsaid casing and having its inlet communicating with the interior thereofand having its outlet arranged to deliver air to said smokehouse, meansarranged in said casing at the end thereof opposite from said supply fanand forming a supply chamber and an exhaust chamber therein, said supplychamber being in communication with said inlet of said supply fan andsaid chambersan outside air damper controlling the admission of saidoutside air to said supply chamber, means for admitting return air fromsaid smokehouse jointly to saidsupply and exhaust chambers, a return airdamper controlling the admission of said return air to said chambers, anexhaust fan secured to said casing and discharging said return air fromsaid exhaust chamber, an exhaust damper controlling the discharge ofreturn air by said exhaust fan, heating coils arranged in said casingbetween said inlet of said supply fan and said supply chamber forheatingthe outside and return air drawn into said supply fan, a volume controldamper arranged in said casing intermediate said heating coils and saidsupply fan inlet and controlling the volume of said return and outsideair drawn into said supply fan, means for regulating said volume controldamper, means arranged between said heating coils and supply fan foradmitting smoke to said return and outside air drawn into said supplyfan, a. smoke damper controlling the admission of said smoke to saidsmoke admitting means, means for regulating said smoke damper, meansresponsive to the dry bulb temperature of .the air in the smokehouse andcontrolling the admission of heating medium to said heating coils, andhumidifying means arranged between said supply fan and said volumecontrol dampers to humidify the air supplied by said supply fan to saidsmokehouse: the combination of means responsive to the humidity of theair in the smokehouse and controlling the relative positions of saidreturn air and outside air dampers, means operatively connecting saidlast means with said humidifying means to control the humidity 01' theair in said smokehouse and means responsive to, the pressure of the airin the Smokehouse and controlling the position of said exhaust damper tomaintain a predetermined air pressure in said smokehouse. 7

CHARLES N. DEVERALL

